A seamless tunic knitted bottom up with two buttons on the left shoulder:
It took almost the whole skein of Lion Brand Cotton-Ease with less then 10 meters leftover.
The tunic probably will turn into a vest very soon but it will still be wearable.
I have used short rows for the neckline to make it round and to avoid cutting the yarn too many times.
Also the ruffle edge leaves no room for mistake - it is a baby girl and not a boy, even if she doesn't wear Barbie pink all the time (common misconception I had to fight in the past with my elder DD who preferred blue over pink until age 4).